The conference "Neural Mechanisms in Cardiovascular Regulation" is a long-running FASEB Summer Research Conference previously held in 1982, 1984, 1987, 1990, 1994, 1996, 1999 and 2002. The previous conferences have been well attended and their value recognized by leading investigators in the field. The topic is widely recognized as an important area of research. The nervous system plays a major role in regulation of arterial pressure, modulation of cardiac and renal function, and occurrence of syncope, cardiac arrhythmias and sudden death in pathologic states. The field is of interest to basic scientists interested in fundamental neural mechanisms, integrative physiologists, and clinical investigators interested in mechanisms of cardiovascular dysregulation in disease. This proposal for the FASEB Summer Conference 2004 will focus on understanding the central mechanisms involved in the physiological and pathological responses of the cardiovascular system to challenges from the external and internal environment. As articulated in 1932 by Walter B. Cannon in "The Wisdom of the Body", the ability of systems to adapt to environmental challenges and maintain homeostasis is fundamental to sustaining life. The scientific sessions for the 2004 FASEB "Neural Mechanisms in Cardiovascular Regulation" Summer Conference are tied together under the subtitle Environmental Challenges and Cardiovascular Regulation in Health and Disease. Each session will cover a specific external or internal environmental challenges and the responses of the neural mechanisms that are engaged to regulate cardiovascular function. Speakers for each session will span each topic from the identification of the challenge to human health to the understanding of the molecular and cellular mechanisms involved. Approximately 160 conference attendees will be selected from interested applicants. The conference will include 4 plenary sessions consisting of 2-3 presentations each, extended discussion sessions, and poster presentations. The plenary sessions include: 1) Osmotic Challenge and Body Fluid Regulation; 2) Steroid Hormone Challenges and Central Regulation of Cardiovascular Function; 3) Respiratory Challenges and Neural Control of the Circulation; and 4) Exercise Training, Temperature Stress and Neural Control of the Circulation. The majority of invited speakers have already agreed to participate and participation of young investigators will be encouraged. Time will be allotted for informal discussions and social interaction. Scientists from the United States and other countries, young investigators, and women are well represented in the program.